Elgin 12 hp only firing on one cylinder

[bbtruck01]

195? model #571.58981<br /><br />5-7.5-12hp with key throttle lock<br /><br />I can't figure out what is wrong. The motor has been running fine. I took it out the other night and tried to start it and it backfired. Now it only runs on one cylinder, occasionally the other will kick in but won't stay firing.<br /><br />I changed the plugs and fuel. The second cylinder spark plug fires off and on. The spark plugs are Autolite 216. The prior plugs were Champion J8JM.<br /><br />Any suggestions will be GREATLY appreciated!!<br /><br />Thanks!<br />bbtruck01

 

[steelespike]

Re: Elgin 12 hp only firing on one cylinder

More than likely it is simply a failed coil. <br /> But when it backfired it may have damaged the flywheel key.<br /> You need to give it a tune up anyway.<br /> Pull the flywheel and check the key for damage.<br />Then clean and adjust the points to .020.<br /> Check the coils for cracks and oxidation.<br />Check the sparkplug wires for corrosion where <br />they go into the coils and at the plug ends.<br />My old manual only goes back to 60 but lists H8J<br />plugs,probably H8C now.Plug gap is .030.